Suspension system for road vehicles and the like



April 8, 1947.

SUSPENSION SYSTEM FOR ROAD VEHICLES AND THE LIKE L. M. BALLAMY ET AL 5 Sheets-Sheet 1 19 16C! 17 19a 12 2 9 .I."

2:117:51 13:31:; :55 26" 61 58 5g; I IIIH [IfiIIII/ $13 54 60 59 LesZze%BaZhz/q April 8, 1947. L. M. BALLAMY ET AL 2,418,744

SUSPENSION SYSTEM FOR ROAD VEHICLES AND THE LIKE Filed Oct. 18, 1943 5 Sheets-Sheet 2 April 1947. 1.. M. BALLAMY ET AL 2,418,744

EM FOR ROAD VEHICLES AND THE LIKE SUSPENSION SYST 5 Sheds-Sheet 3 Filed Oct. 18, 1943 mm Nm QN Patented Apr. 8, 1947 SUSPENSION SYSTEM FOR ROAD VEHICLES AND THE LIKE Leslie Mark Ballamy, Caterham, and Richard Hasell Sheepshanks, Eyke, Woodbridge, England Application October 18, 1943, Serial No. 506,740 In Great Britain October 23, 1942 11 Claims. 1

This invention relates to suspension systems for road vehicles and the like, and it has for its primary object to provide an improved form and construction of suspension which is intended more especially for use in conjunction with the rear wheels of motor vehicles.

In a mounting system for a pair of coaxial wheels of a vehicle, comprising a transverse member upon the end parts of which the wheels are rotatably mounted, resilient means being provided to urge the wheels downwards relative to the body or equivalent for transmitting the load resiliently to the wheels, the present invention is characterised by the fact that the transverse member is anchored to the vehicle body or equivalent by a pivotal connection enabling said member to rock bodily about a fore and aft axis substantially midway between the Wheels, and also to move angularly about a transverse axis for allowing the wheels to rise and fall relative to the vehicle body or equivalent, for which purpose the said transverse axis is disposed behind or before the common wheel axis.

The pivotal mounting of the transverse member can conveniently be disposed behind a differential gear unit by which the wheels are driven.

Preferably the pivotal mounting of the transverse member is provided with means for locating said transverse member against displacement in a transverse direction. The transverse member may comprise a substantially straight transverse portion having at each end an arm which is directed substantially parallel with the longitudinal axis of the vehicle, a vehicle wheel being mounted upon each of said arms. Further, the transverse member may be attached to the nonrotating part of a brake associated with each of a pair of wheels, said transverse member being arranged to resist the braking torque. The trans verse member conveniently comprises a hollow support through which a torsion bar extends, said bar connecting together a pair of arms pivotally carried at the ends of the hollow support. The pivotal connection for the transverse member preferably includes a sleeve of rubber or like resilient material adapted to act in torsion to permit angular movement of the transverse member;

the latter may be anchored to the vehicle body or equivalent by a universal mounting comprising an intermediate member pivoted to the ve-- hicle body or equivalent and to the transverse member, respectively, by a pair of rubber or like resilient bushes having their axes mutually at right angles. If desired the resilient means may comprise a transverse spring which is secured at its central portion to the vehicle body or equivalent, and its ends co-operate with the arms to urge the wheels downwards relative to said vehicle body or equivalent, the ends of the transverse spring conveniently being secured to the arms and thus helping to locate said arms against transverse movement, and also movement longitudinally of the vehicle. Alternatively the resilient means may comprise a pair of suspension devices of the kind having a working space which latter contains gas under pressure and has its volume reduced as the wheels move upwards rela- Figure 5 is a detail sectional elevation taken 0 1 the line 5-5 of'Figure 4;

Figure 6 is a sectional elevation of one arm, taken on the line 6-6 of Figure 3; and

Figure 7 is a fragmentary plan of another arrangement, also partly in section.

In Figure 1 the two coaxial rear Wheels of a vehicle are indicated at I 0 and II, respectively.- They are rotatably mounted upon the end parts of a transverse member l2, which end parts are arranged to extend in a forward direction soas to constitute a pair of arms l3 and It. The wheels I0 and II are driven by telescopic live axles l5 and I6, respectively, from a differential gear unit l'l mounted upon the chassis, bodyor equivalent of the vehicle, i. e. upon the sprung portion of"' the vehicle. The central part of the bodywhere it carriesthe difierential gearunit H is indicated differential unit ll, which latter is driven in the usual manner by a propeller shaft [9.

In order that the vehicle body or equivalent may be supported in a resilient manner the forward ends 20 and 2! of the arms I3 and M are connected with the sides of vehicle chassis, body or equivalent at 22 (see Figure 2) by means of telescopic suspension devices of the known pneumatic or Olen-pneumatic type, these being indicated at 2;3:and 24 The central portion ei an verse memb r 82 is anchored to the differential unit I! by means of a universal joint 25 comprising a substantially T-shaped intermediate member 25, The member I2 passes through the transverse "limb of their;- termediate member and is free to turn therein, axial displacement (i. e. in La di-rection (transversely of the vehicle) being preventeid ;by :a pair of thrust collars 21 and 2-8. The intermediate member 26 is also pivoted to thesdifierential unit I! so as to be free to pivot aboutahQr-izontal axis 29 extending in a direction longitudinally of the vehicle. It will thus be seen that the transverse member l2 maintains the wheels H1 and H :in azstrictly coaxial relationship, 1 but enables eithermne. or'both :of :them, .torise and I all relat verto-lthevehicle bodym'a emvalent, this-assumn of course, that the transverse vmember i2 is ".121 :asmmpletelv ri id nature. For instan when zone :of the wheels vstrik s a bump and is iorced -;u wards, theitransverse member 42 can move ,aneularlv about th lon itud nal axis 29; if both wh els strike :a transverse ridge in th mad surfiacethenthe tran verse member (21emainsihoriaontalnbutmovesan ul rlv about the axisnt its ransversepartindicatedxat 3t.

2111 rractiee the "tran v rse mem er l 2 l an v a.d vantas eusly be d igned so that i s transv rse 'hascarn tede erm ned am un of resilartors nna sense,;thus'-.enabl n the end portions nrrarms :43 a V 1.4 to .rise andrfall to a s ht ext ntsrelat ve-t pne-amtherwithout apnreeiab v a fect ng the mutually :p allel relatienshinef Lll 1Wl i .rlflsand ;l i ffhiszisz usef for enabling smooth running to be readily jobainednverrq dshav nsnnlvsliehtsirregularities, for each wheel is capable .pf -;osci ll at-ing ;;rgapidly atzs sht ampl tude-withoutafiectine:the disp sition of the other wheel. Where the-wheels ll] and :U ere-p ovided with brake 3.! and :32 the back plates or other fixed parts,of: s aid-]or akes may advantageously ELLE secured to e arms l3 and I s thattm transversemem er :12 serves t prov de the requis te :reantion t r sist the braking torque.

1n the const uctional arrang m nt shown in F res 3 tofi the vehic e chassis comprisesanair of l n itud nal m mb rs .35-and136 spa d by a relatively small distance :and braced to ether to form a long t di al backbone upon which-the vehicle body is mounted. The diiierential unit I1 is als seemed between the members ,35 and B and .is driven by a p emhenshaft 119, :thesoutpu from-the diiieren ial unit ii to the wheels ,0 and ..'l .l .be eat ken th ouehtelescep c live axles I5 and :1 having vuniv r al Joints at Ill. The Wheels .10 and ,l 5| ,are rotatahly mounted upon the forward lends cf a m 3 and 1:4, to which latter the lnonerotatingparts i th brak s 3;! and 3 are secured :by flanges ,fi-l and 3t.

*illhestransverse member vl. iseqf eompe ite ,ferm andicon prises atubul pu ter ca ing :39 which i mount d .bysmeans of 1a ruhberierlike resilien bush All to m re angul rlyabouta transverse axis within an intermediate member 25. As will be seen in Figures 4 and 5, this intermediate member 26 is formed with a pair of depending ears ll, by which it is connected with a transverse bracket 42 secured between the chassis members 35 and 36; in order that the transverse member l2 may be free to rock about a longitudinal axis a rubber bush bearing 43 is interposed between the bracket i2 and a bolt as passing through the ears ll. The bracket 42 is integral with the longitudinal members 35, 36, which latter are sloped down- Wards at their rear partsas shown in Figure 5 to clear the transverse member I2, and are pro- -,vided with a transverse bridge portion 32a.

,Upon the rear part of each of the arms 13 and l l-anylindrical-spigot 45 is formed and fits rotatably within the corresponding end part of the transverse tube 39, ;a bearing bush 46 being pro- .videddto'reduce wear. The end part of the spigot 45 is in each caseformed with a splined recess 41 to receive the end part of a straight torsion rod tsiextendingaxially through the transverse tube 39, the arms 13 and 14 being securely clamped tosa-idtorsion bar by means of bolts 49 and 50. Each arm is flanged at 5| and is provided with a thrust washer-52, which isengaged by a screwthreaded-sleeve 53 mounted upon the end'part of the tube 39. -A transverseilaminated half-"elliptic spring 5.4 is secured at its centre part to the bridge portion 52a ofthe chassismembers 135-and 38, while its ends are clamped to depending projections 13a and Maupon the arms 43 and M respectively by bolts 55 and 56, whereby said spring 54 serves to prevent displacement of the arms 83 and I l-(and the wheels is and H carried thereby) in a direction transversely ofthe vehicle, and for this reason it is unnecessary tolprovide means for-preventing axialmovement of thewtube 39 relative to the universal joint.2-5.

The torsion rod 48 is arranged :tobe relatively stifi, so-thatthe arms-i3 and Minormally tend .to move upwards and downwards in unison when the wheel movements are substantial, but as .said torsion rodis normallyin anzunstressedconditime (i. e., i;s n0.t pro-stressed durin assembly) it;f.01l WS that slight verticalmovements-of:each arm ts or M can occur Withoutaficctlllg the other arm, the movements being enabled to take place owing to the resilience of theatorsionrod 48. -Nevertheless the transverse tube -39 at all times maintains the wheels wand ii in planes WhiQh EblfQ substantially parallel-with one another, and this condition is also-maintained even when the vertical wheel movements have a 1argeam plitude. In thesellatter circumstances, however, the torsion rod dBlargely makes thearms I13 and L4 move upwards and downwards in unison, so that themovements of each wheel are-restrained by the inertia of the other.

In themodification shownin Figure 7 the arms 13 and M pointina rearward direction from the nds of the transverse member 12, and eachis of hollow construction so as :to hcusea train of gear wheels 57, :58 and 15.9. The gear wheel e!) is connected directly with the corresponding road wheel H3 or H and is driven by the gear wheel 5'! through the wheel 58, which is an idler. The differential unit ll is in this instance .mounted bodily upon an intermediate member .25 so as to be .angularly movable about a transverse axis,

the intermediate member itself being pivotally connected at: 6 I to anzanchoragemember fifltforming part I of the vehicle chassis or body; the intermediate member 26 is thus free to move :angularlyabout a longitudinal axis, The transverse member (2 is constituted by a pair of coaxial tubes I21; and I2!) both secured rigidly to the easing of the differential unit I1, the whole producing an assembly which resembles the differential and rear axle casing of the usual motor car. The arms l3 and [4 are rigidly attached to the tubes l2a and I2!) respectively, driving shafts I 6a and 16b from the differential unit I! being connected respectively with the gear wheels 5'! of the arms. As the difierential unit is free to move, the driving shaft i9 is provided with a universal joint I9a, The Weight of said body is transferred to the wheels I0 and H by means of a semi-elliptic laminated spring 54 conveniently secured at its centre part to the anchorage 60, while its ends are clamped to the arms l3 and I4. Instead of the gearing 51-59, a chain drive could be used for transmitting the drive along each of the arms l3 and M.

It will be seen that with the improved arrangement the unsprung weight amounts to very little more than the mere weight of the wheels and brakes, and yet the two wheels are at all times efficiently retained in parallel planes; also, except for slight inequalities in the road surface the wheel axes are maintained efficiently in alignment by the axle member and the two arms fitted at'opposite ends thereof.

What we claim is:

l. A mounting for the rear wheels of a motor vehicle, including a stiff but torsionally resilient transverse member having at its middle an attachment to the vehicle body to prevent vertical movement of the transverse member relative to the vehicle body at the point of attachment, while allowing said transverse member to rock in a vertical plane about its middle, and to revolve about a transverse axis, a pair of arms extending from the transverse member substantially parallel with the longitudinal axis of the vehicle and carrying the said driving wheels, the torsional resilience of the transverse member enabling the arms to move angularly one relative to the other in mutually parallel upright planes, brakes upon the wheels having their non-rotating parts anchored to the arms so that said arms provide the brake reaction, and resilient suspension means between the vehicle body and the arms displaced from the transverse member, to press the arms downwards and thus apply the body load to the wheels.

2. A mounting for the rear wheels of a motor vehicle, including a stiff torsionally resilient transverse member having at its middle an attachment to the vehicle body, to prevent vertical movement of the transverse member relative to the vehicle body at the point of attachment, while allowing said transverse member to rock in a vertical plane about its middle, and to revolve about a transverse axis, a pair of arms extending forwardly from the transverse member and carrying the said driving wheels, the torsional resilience of the transverse member enabling either of the wheels to rise relative to the other by moving the corresponding arm angularly and thus twisting the transverse member, brakes upon the wheels having their non-rotating parts anchored to the arms so that said arms provid the brake reaction, and resilient suspension means between the vehicle body and positions on the arms forward of the transverse member, to urge the arms downwards about the said transverse axis of mounting of the transverse member, and thus apply the body load to the wheels.

3. A mounting for the rear wheels of a motor vehicle, including a transverse member having at an intermediate point an attachment to the vehicle body to prevent vertical movement of the transverse member relative to the vehicle body at the point of attachment, while allowing said transverse member to rock in a vertical plane about its middle, and to revolve about a transverse axis, a pair of arms extending forwardly from the transverse member and carrying the said driving wheels, brakes upon the wheels having their non-rotating parts anchored to the arms so that said arms provide the brake reaction, and resilient suspension means between the vehicle body and the arms forward of the transverse member, to urge the arms downwards about said transverse axis of mounting of the transverse member and thus apply the body load to the wheels.

4. A mounting according to claim 3, including a difierential gear box by which the wheels are driven, the pivotal mounting of the transverse member being attached to the said differential gear box, at the rear thereof.

5. A mounting according to claim 3, wherein the transverse member comprises a tubular support, and a torsion bar disposed within said support, said bar connecting together the pair of arms, which latter are pivotally mounted upon the ends of the tubular support.

6. A mounting for the rear wheels of a motor vehicle, including a transverse member having at its middle an attachment to the vehicle body, to prevent vertical movement of the transverse member relative to the vehicle body at the point of attachment, while allowing said transverse member to rock in a vertical plane about its middle, and to revolve about a transverse axis, a pair of arms extending forwardly from the transverse member and carrying the said driving wheels, brakes upon the wheels having their non-rotating parts anchored to the arms so that said arms provide the brake reaction, and a transverse leaf spring attached at its center to the vehicle body and acting at its ends, respectively, upon the arms at positions thereon forwardly of the transverse member, to urge the arms downwards about said transverse axis of mounting of the transverse member and thus apply the body load to the wheels.

7. A mounting according to claim 6, wherein the ends of the transverse leaf spring are attached to the arms and thus locate said arms against transverse movement, and against movement longitudinally of the vehicle.

8. A mounting for the rear driving wheels of a motor vehicle, including a transverse member having at its middle an attachment to the vehicle body, to prevent vertical movement of the transverse member relative to the vehicle body at the point of attachment, while allowing said transverse member to rock in a vertical plane about its middle, and to revolve about a transverse axis, a pair of arms extending forwardly from the transverse member and carrying the said driving wheels, brakes upon the wheels having their non-rotating parts anchored to the arms so that said arms provide the brake reaction, and a pair of telescopic suspension devices supporting the load of the vehicle by pneumatic pressure, said suspension devices being connected respectively between the vehicle body and positions on the arms forwardly of the transverse member, to urge the arm downwards about said transverse axis of mounting of the transverse member and thus apply the body load to the wheels.

9. A mounting according to claim 8, in which the telescopic suspension devices are attached to 7 e the arms at positions forwardly of the wheel axis. REFERENCES CITED A construction as definedin claim 8, Where The following references are of record in the in a, difi'erential gear for driving the wheels is fil of t patent: mounted upon the vehicle body and forms the said UNITED STATES PATENTS attachment for the transverse member. 5

11. A construction as defined .in claim 8, where- Number Name Date in means are provided at the attachment of the 2256069 Wagner sept- 1941 transverse member to the vehicle body for pre- 1,331,862 Horme 1931 venting transverse displacement of the transverse 7842591 Thompson et 1907 V 10 2,083,085 Palmer June 8, 1937 member- '2,328;740 Reimspiess Sept. 7, 1943 2,184,Q33 BIOWI] DEC, 26, 1939 LESLIE MARK BALLANIY. 2,286,609 Ledwinka June 16, 1942 RICHARD HASELL SHEEPSHANKS. 2,330,541 Barenyi Sept. 28, 1943 

